• Fisheries and Aquatic Sciences
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• 제1권2호
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• pp.180-186
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• 1998

A 10-week feeding experiment was conducted to determine the phosphorus requirement of juvenile Korean rockfish (Sebastes schlegeli). Three replicate groups of fish initially averaging 4.2g were fed the semipurified experimental diets containing graded levels of $NaH_2PO_4\;\cdot\;2H_2O$ to provide from $0.1\%$ to $1.32\%$ total phosphorus level in a flow-through seawater system. Korean rockfish muscle and casein were used as the protein sources of the basal diet. Weight gain, feed efficiency and protein retention of fish fed the $0.35\%$ phosphorus were higher than those of fish fed the $0.1\%$ phosphorus, although no significant improvements $(P>0.01)$ were observed above the level. Determined phosphorus requirement using the broken line model was found to be $0.3\%$ for weight gain. Moisture, protein and lipid contents of whole body and muscle were not affected by dietary phosphorus levels $(P>0.01)$. Lipid contents of liver in fish fed the $0.1\%$ phosphorus were lower than those in fish fed the $0.35\%$ and $1.32\%$ phosphorus $(P<0.01)$. Dietary phosphorus increased ash and phosphorus contents of the whole body, while those of bone were not affected $(P>0.01)$. The data obtained in this study indicate that a $0.3\%$ dietaryphosphorus level could be recommended for the optimum growth and efficient nutrient utilization of juvenile Korean rockfish.

• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.89-96
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• 1998

The experiment was conducted with 120 barrows weaned at 21 days of age to estimate their lysine requirement weaned at 21 days of age when other important amino acids were fortified to get optimal ratio to lysine. The treatments were 1.15% (control), 1.25%, 1.35%, 1.45%, 1.55%, 1.65% total lysine in the diet. Based on the growth performance total lysine requirement of 21-day old pigs appears to be 1.45%. The lowest digestibilities of dry matter and crude fat were found in pigs fed 1.15% total lysine diet and the highest were found in pigs fed 1.65% total lysine diet with no significant differences among treatments. Nitrogen digestibility increased as the total lysine level increased up to 1.35% (p < 0.05) and remained relatively constant beyond 1.35%. However, the best nitrogen digestibility was observed in pigs fed 1.45% total dietary lysine. Gross energy, crude ash and phosphorus digestibilities did not differ due to the increase in total lysine level. The amounts of excreted dry matter and nitrogen differed significantly by the increase in lysine level up to 1.35% (p < 0.05), while phosphorus excretion was not influenced by the lysine level. Dry matter and nitrogen excretion were reduced by 13.6% and 18.4%, respectively, when 1.45% lysine was offered to the pigs compared to the those fed on 1.15% lysine diet. The amino acid digestibilities increased as the total lysine level increased up to 1.45% (p < 0.05), and remained constant beyond 1.45%. The lysine requirement for the pigs weighing 6 to 14 kg seems to be higher than the previous estimates and in order to reduce pollutant excretion the accurate nutrient requirement should be set and applied to the animal.

• Asian-Australasian Journal of Animal Sciences
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• 제2권3호
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• pp.261-263
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• 1989

• 한국토양비료학회지
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• 제16권1호
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• pp.64-71
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• 1983

강산성(强酸性) 토양(土壤)인(pH 3.5) 특리산성답(特異酸性畓)에서 석회(石灰)와 인산(燐酸)의 시용(施用)이 토양(土壤)의 변화(変化) 및 수량증대(收量増大)에 미치는 효과(効果)를 구명(究明)하기 위(為)해 시험(試験)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 석회중화량(石灰中和量) + 인산(燐酸) 20/10a구(区)에서 무처리구(無處理区)에 비(比)해 수량구성요소(收量構成要素)를 증대(増大)시켜 60%의 증수효과(増收効果)가 있었다. 2. 수량증대(收量増大)에 미친 효과(効果)는 석회(石灰)는 36%, 인산(燐酸)은 15%로써 석회(石灰)의 시용효과(施用効果)가 컸다. 3. pH와 Eh에 있어서는 석회시용량(石灰施用量)이 많을 수록 pH는 높아졌고 반대(反対)로 Eh는 낮아졌으며 석회(石灰)와 인산(燐酸) 시용(施用)은 토양환원(土壤還元)을 촉진(促進)하였다. 4. 근(根)의 신장(伸長)은 무석회구(無石灰区) 논 표토(表土) (0~5cm)에 62%의 뿌리가 존재하였으나 석회(石灰)와 인산(燐酸)을 많이 시용(施用)할수록 하위(下位)(5~10cm)까지 뻗어갔다(60%). 5. 토양(土壤) pH변화(変化)는 최고분얼기(最高分蘖期)에 최고(最高)에 이르며 그 후 점차 감소하여 원(原) pH값에 접근하였으나 석회 소요량은 약(約) 반(半)이였다. 6. 토양중(土壤中) 규산(珪酸), 인산(燐酸)과 수량(收量)은 유의성(有意性)있는 정(正)의 상관(相関)으로 나타났고 pH를 높여줌으로 토양중(土壤中) 규산(珪酸)과 인산(燐酸)의 함량(含量)을 높여줄 수 있다. 7. 석회(石灰)와 인산(燐酸) 증시(増施)는 질소흡수(窒素吸水)를 증가(増加)시키고 식물체중(植物体中) 인산(燐酸)의 흡수(吸水)가 많을수록 수량(收量)은 증가(増加)한다.

• Journal of Applied Biological Chemistry
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• 제44권1호
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• pp.16-19
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• 2001

Soybean plants(Glycine max [L.] merr.) inoculated with Bradyrhizobium japonicum MN110 were grown in growth chambers under 400 or $800{\mu}l{\cdot}l^{-1}$ atmospheric $CO_2$ and harvested at 25, 28, 32, and 35 DAT to examine the effect of $CO_2$ enrichment on phosphorus accumulation, uptake, and utilization efficiency during vegetative growth. Phosphorus concentration in leaf was lower in high $CO_2$ plant by 47% at 25 DAT and 34% at 35 DAT than those in the control plant but phosphorus concentrations in stem, root and nodule were not affected by $CO_2$ enrichment. Total phosphorus accumulation increased 3.9-fold in high $CO_2$ plant and 3.2-fold in the control plant between 25 and 35 DAT. Elevated $CO_2$ caused a decrease in the whole plant phosphorus concentration by 35%, which was due almost entirely to a decrease in the phosphorus concentration of leaves. $CO_2$ enrichment increased phosphorus utilization efficiency in the whole plant by 70% during the experimental period. Plants exposed to high $CO_2$ had larger root systems than under ambient $CO_2$, but high $CO_2$ plants had lower P-uptake efficiency. Averaged over four harvests, plants at high $CO_2$ had 38% larger root mass that was more than offset the 20% lower efficiency of P-uptake and accounted for increased phosphorus accumulation by high $CO_2$ plant. These results suggest that the reduced phosphorus concentration in soybean plant under $CO_2$ enrichment may be an acclimation response to high $CO_2$ concentration or enhanced starch accumulation, resulting in the plants to have a lower phosphorus requirement on a unit dry weight basis or a high phosphorus utilization efficiency under these conditions.

• Asian-Australasian Journal of Animal Sciences
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• 제26권9호
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• pp.1282-1288
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• 2013

A comparative slaughter trial was conducted to estimate the phosphorus (P) requirement for maintenance and growth of crossbred lambs of Dorper with a Chinese indigenous sheep breed, thin-tailed Han sheep. Thirty-five Dorper${\times}$thin-tailed Han crossbred, noncastrated ram lambs ($20.3{\pm}0.22kg$ of shrunk body weight (SBW)) were used. Seven lambs were randomly chosen and slaughtered at 20 kg SBW as the baseline group for measuring initial body composition. Another seven lambs were also randomly chosen and offered a pelleted mixed diet for ad libitum intake and slaughtered at 28 kg SBW. The remaining 21 sheep were randomly divided into 3 groups with 7 sheep each and subject to the same diet of either 70 or 40% of ad libitum intake. The 3 groups were slaughtered when the sheep fed ad libitum reached 35 kg of SBW. Body P contents were determined after slaughter. The results showed that the net P requirement for maintenance was 30.0 mg/kg of empty body weight (EBW) or 23.4 mg/kg body weight (BW), and the P requirement for growth decreased from 5.3 to 5.0 g/kg of EBW gain as the lamb grew from 20 to 35 kg. The net P requirement for growth of Dorper${\times}$thin-tailed Han crossbred ram lambs was lower than that of sheep adopted by the American nutritional system.

• 상하수도학회지
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• 제27권4호
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• pp.439-444
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• 2013

Excessive phosphorus in aquatic systems causes algal bloom resulting in eutrophication, DO depletion, decline in recreational value of water and foul tastes. To treat wastewater containing phosphorus including effluent of wastewater treatment plant, the continuous experiments were performed by using electrochemical way. The spherical ZVI and silica sand which act as physical filter are packed at appropriate volume ratio of 1:2. Electric potential is applied externally which can be changed as per the operational requirement. The results indicate that optimum hydraulic retention time of 36 minutes (10 mL/min at 1 L reactor) was required to meet the effluent standards. Lower concentrations of phosphorus (<10 mg/L as phosphate) were removed by precipitation by contact with iron. Thus, additional electric potential was not required. In order to remove high concentration phosphorus around 150 mg/L as phosphate, external electric potential of 600 V was applied to the reactor.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.755-768
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• 1998

Nitrogen and phosphorus are major nutrients in animal feeds which partially remain in the environment as pollution. In addition, nitrogen and phosphorus along with energy are the main nutrients which determine the feed cost. Any decreases in the levels of these three nutrients can contribute to reducing the pollution problem as well as the cost of feed. The nutrient requirements for chickens in the work here reported should allow for the addition of mixed enzymes (phytases, proteases, glucanases, xylanases and others). Such minimal levels of crude protein in the research results which are here reported are 16% for 0-6 weeks of age, 13.5% for 7-12 weeks of age, 11.5% for 13-18 weeks of age for layer type chicks, 13% for layer, 18% for 0-3 weeks of age broiler and 16.5% for 4-7 weeks of age broiler. These research projects have been done without adding enzyme supplements to their experimental diets. The minimal values of phosphorus, shown as available phosphorus, are 0.25% for pullets, 0.09% for layers and 0.25% for broilers with the addition of phytase. The minimum energy requirement (metabolizable energy) for reducing the feed cost could be summarized as 2,750 kcal per kg feed for pullets, 2,800 kcal for layers and 2,700 kcal for broilers.

• 한국가금학회지
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• 제8권2호
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• pp.55-68
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• 1981

칼슘과 인은 동물의 골격형성 및 반 평형유지에 필수적일 뿐 아니라 란각의 중요간 구성물질이다. 그러나 가금의 주요 원료사료인 식물성사료는 대부분 칼슘과 인의 함량이 낮으며 그 이용성도 낮아 별도로 추가공급이 필요하다. 따라서 칼슘과 인의 기능을 밝히고 요구량을 찾아내며, 그 공급원 및 이용성을 조사하는 것은 매우 중요하다. 이제까지 칼슘과 인의 영향적 특성 및 공급에 관해 고찰하였는 바 결과를 요약하면 다용과 같다. 1. 칼슘과 인은 정상적인 기능을 수행하기 위해 비타민D 및 Na 등과 긴밀한 상호작용을 가지고 있다. 2. 대부분의 식물성 사료내에 들어 있는 인은 피 틴태로서 단위 동물에는 이용성이 낮으며 가축의 년령이 증가하거나 비타민D$^3$의 급여가 증가하면 피틴태 인외 이용율도 다소 증가한다. 일반적으로 동물성사료 및 무기가물사료내 존재하는 칼슘과 인은 이용성이 상당히 높다. 3. 가금의 칼슘과 인의 요구량은 부로일러 및 산란용 초생추의 경우 칼슘 1.0% 인 0.7% 내외이며. 산란계의 경우 칼슘 3.5% 인 0.4% 수준으로 요약되었는데 이는 최근 NRC(1977)의 요구량 수준과 비슷하다. 4. 칼슘과 인의 공급은 사료섭취량이 적은 경우 공급수준을 증가시켜 주는 것이 바람직하며 산란계의 경우 산란율이 높거나 년령이 오래된 닭의 경우 칼슘의 급여량을 증가시켜 3.75%까지 급여하는 것이 좋다. 실제 사육시에는 칼슘과 인의 이용율을 고려하여 요구량 수준보다 20%정도 증가시켜 주는 것이 바람직하다. 5. 칼슘과 인 공급제의 이용성은 제1, 제2, 제3 인산칼슘. 탄산칼슘, 골분, 석회석, 패분등이 가장 우수하였으며 연인광석, 탈불인광석, 석고등은 다소 떨어졌다. 산란계의 경우 칼슘공중제로서 방해 석은 석회석이나 패분과 비교해 볼때 거의 같은 효과를 가지는 것으로 나타났다. 따라서 방해석은 새로운 칼슘공급제로서 효과적으로 사용될 수 있을 것이다. 6. 칼슘공급제의 입자도가 산란능력에 미치는 영향은 아직 확정지을만한 결과를 얻지 못하고 있으나 일반적으로 패분은 입자도가 굵을때 석회석은 입자도가 미세할 때 산란능력이 우수하였다. 7. 산란계에 있어서 패분과 석희석을 단용 하는 것보다 혼용하면 그 이용성이 증가하였다. 8. 사료내 Na의 농도가 높으면 인의 급여량도 높여 주는 것이 산란능력 향상에 도움이 되었으며 Na수준이 낮은경우는 인의 급여수준도 낮추는 것이 바람직한 것으로 나타났다.

• 한국토양비료학회지
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• 제10권2호
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• pp.93-97
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• 1977

최선(最善)의 인산시용량(燐酸施用量) 결정기준(決定基準)을 찾고저 기경지(旣耕地), 미개간지(未開墾地) 및 제주(濟州) 화산회토양(火山灰土壤)을 공시(供試)하여 충분(充分)한 관수조건하(灌水條件下)에서 콩을 재배(裁培)한 pot시험결과(t試驗結果)를 요약(要約)하면 다음과 같다. 1. 토양별(土壤別) 인산흡착력(燐酸吸着力)의 차이(差異)를 가장 잘 나타내는 지표(指標)는 Langmuir 최대인산흡착량(最大燐酸吸着量)이었다. 2. 최대인산흡착량(最大燐酸吸着量)는 초산(酢酸)암모니움 침출(浸出) Al 함량(含量)에 비례하나 제주도(濟州道) 토양(土壤)에서는 Al외(外)에 유기물함량(有機物含量)의 영향(影響)이 컸다. 3. 최대수량(最大收量)을 얻기 위한 인산시용량(燐酸施用量)은 인산최대흡착량(燐酸最大吸着量)의 30~50% 범위에 있었다.